Now that Art Deco buildings are 50 years old and Federal, State, and Municipal agencies have designated these buildings as landmarks, there is a need for appropriate replacement windows for the non-insulated, leaky (and even disintegrating) windows used in those buildings. The original windows were slim steel casements that represented modernity and high technology to architects working in the Bauhaus, Art Deco, and Streamlined styles. Preservation regulatory agencies require that the original appearance be maintained in these "significant" buildings. The agencies' mandate covers the less numerous but equally "significant" Tudor and Gothic revival buildings as well.
The replacement window must be compatible aesthetically with the architecture of that era. Also, desirably, the design should be responsive to current industry and government standards.
Aesthetically, the steel window appearance to be replicated comprises:
1. a two inch masonry-to-glass perimeter sightline; PA0 2. a three inch glass-to-glass sightline at primary operable-to-operable and operable to fixed framing members; PA0 3. a putty slope, mitred corner appearance around each operable and fixed light with exterior face of glass set back one inch from face of exterior of window frame; PA0 4. an uninterrupted narrow reveal around casement leaves; and, PA0 5. endless elevation layouts combining fixed and operable lights, where operable lights are virtually indistinguishable from fixed lights.
Current industry and government standards require replacement windows: to minimize energy losses (therefore thermal breaks and insulating glass are desired); to permit interior glazing and reglazing; to have maintenance free finishes; to enable the utilization of standard hardware, including cleaning hinges, locks, etc.
Prior to the present invention there have existed several approaches to manufacturing a window which replicates the architecturally desirable appearance of the outside putty glazed, outswinging steel windows used in buildings of earlier eras; or which incorporates current industry and government mandated performance criteria. However, no one design accomplishes everything.
For example, techniques for replicating these steel windows prior to the present invention have comprised:
1. manufacturing them from similar new, steel shapes, which are outside, putty glazed. This approach creates cost and safety problems attendant upon exterior glazing and reglazing and exterior painting, especially so on high-rise buildings. Further, the use of insulating glass is prohibited.
2. Manufacturing them from extruded aluminum shapes. This has been accomplished easily for wholly fixed windows by incorporating the mitered corner, putty-bevel recessed glass look into the aluminum extrusion. This fixed window incorporates thermal separation, permanent exterior finishes, interior glazing and reglazing capability of insulating glass. The same low (2") sight-line and performance features can be incorporated into a single casement or projected ventilator in its own frame, but cannot be integrated with another ventilator or fixed light in a single frame.
3. Manufacturing them from aluminum by a process generally termed "architectural metals". By this means, windows with an outside putty glazed, steel window appearance can be custom fabricated, virtually hand-made, in any combination of fixed and operable lights as of old. They can even incorporate thermal separation, insulating glass, interior glazing and reglazing and permanent finishes. And, in spite of the fact that aluminum is only 1/3 as strong as steel, they can also be made strong enough to withstand windloads and water and air penetration. However, this customized approach cannot incorporate user friendly hardware while simultaneously maintaining high performance standards, since there is just not enough room for the right hardware if the necessary amount of metal for strength is used; and vice versa. More importantly, because this is a customized approach, the issue is academic because windows made in this fashion are far too costly for general acceptance except for use in a few monumental buildings, atriums, etc.
4. Combining in separate frames or integrating into a single frame, commonly manufactured 2" to 21/2" deep, aluminum filed, projected and casement windows, forming a grid identical in function to the old windows. They can be manufactured with universally available mechanical components of proven reliability. Likewise, thermal separation, insulating glass, interior glazing and reglazing and maintenance-free finishes are available and cost-efficient. Aesthetically, however, their appearance is far from that of the steel windows. These conventional operable aluminum windows have 3" to 31/2" perimeter sight lines and 41/2" to 6" internal framing sight lines. The exterior frame is flat with only 3/16" to 5/16" set-back of glass. Separate frames mullioned together create a 6" to 8" glass-to-glass sight line as compared to 4" glass-to-glass for old steel windows. For whatever style building architects intend their use, this flat, wide appearance can intentionally be made part of the overall design. However, where a slim, non-flat appearance is needed for either post-modern or revivalist architecture, or for replacement of old steel windows in architecturally significant existing buildings, conventional aluminum windows are not satisfactory.
Therefore, it is a primary object of this invention to provide a window system which aesthetically replicates the steel window of old; while responding to the performance demands of government and industry.
It is yet another object of this invention to provide a window system which is mass produceable and cost effective for both the retrofit and new construction markets.
It is still yet another object of this invention to provide a window system which permits the combination of fixed and operable lights in a myriad of configurations, limited, virtually, by the architects creativity.